Monitoring veterinary antimicrobial use is part of the global strategy to tackle antimicrobial resistance. The purpose of this study was to quantify veterinary antimicrobials imported into Timor-Leste between 2016 and 2019 and describe the antimicrobial import profile of importers. Data were obtained from import applications received by the Ministry of Agriculture and Fisheries (MAF) of Timor-Leste. Import quantities were analysed by antimicrobial class, importance for human medicine, recommended route of administration and type of importer. An average of 57.4 kg (s.d. 31.0 kg) and 0.55 mg/kg (s.d. 0.27 mg/kg) animal biomass of antimicrobials was imported per year. Tetracyclines (35.5%), penicillins (23.7%), and macrolides (15.9%) were the commonly imported antimicrobial classes. Antimicrobials imported for parenteral administration were most common (60.1%). MAF was the largest importer (52.4%). Most of the critically important antimicrobials for human medicine were imported by poultry farms for oral administration and use for growth promotion could not be ruled out. In conclusion, the use of antimicrobials in animals in Timor-Leste is very low, in keeping with its predominantly subsistence agriculture system. Farmer education, development of treatment guidelines, and strengthening of the veterinary service is important for addressing the potential future misuse of antimicrobials especially in the commercial poultry industry.

The rapid emergence of antimicrobial resistance is a global concern, and high levels of resistance have been detected in chicken populations worldwide. The purpose of this study was to determine the prevalence of antimicrobial resistance in Escherichia coli and Salmonella spp. isolated from healthy chickens in Timor-Leste. Through a cross-sectional study, cloacal swabs and boot swabs were collected from 25 live bird markets and two layer farms respectively. E. coli and Salmonella spp. from these samples were tested for susceptibility to six antimicrobials using a disk diffusion test, and a subset was tested for susceptibility to 27 antimicrobials using broth-based microdilution. E. coli and Salmonella spp. isolates showed the highest resistance towards either tetracycline or ampicillin on the disk diffusion test. E. coli from layer farms (odds ratio:5.2; 95%CI 2.0–13.1) and broilers (odds ratio:18.1; 95%CI 5.3–61.2) were more likely to be multi-drug resistant than those from local chickens. Based on the broth-based microdilution test, resistance to antimicrobials in the Timor-Leste Antimicrobial Guidelines for humans were low, except for resistance to ciprofloxacin in Salmonella spp. (47.1%). Colistin resistance in E. coli was 6.6%. Although this study shows that antimicrobial resistance in chickens was generally low in Timor-Leste, there should be ongoing monitoring in commercial chickens as industry growth might be accompanied with increased antimicrobial use.